ΔE 15.6, loose: different enough that you should pick on purpose. Turquoise Deep is a little darker, warmer than Abyssal Blue.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Turquoise Deep is a little darker, warmer than Abyssal Blue.
The same difference applies the other way round: Abyssal Blue is a little lighter, cooler.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Abyssal Blue on the colour wheel See Turquoise Deep on the colour wheel
All matches: Abyssal Blue equivalents · Turquoise Deep equivalents